Re: Can I retreive it? FWD on Ramp
First, I don't think that you have the right vehicle for the job. Coming up with a "work-around" is certainly possible, but I doubt you will find it to be a satisfactory situation. And, as others have mentioned, all the folks who will have to wait for you to go through all sorts of hooking, unhooking, winch deployment & retreival, chocking, fighting with a trailer tongue dolly that is free floating, and will want get stuck or go its own way with every bump in the ramp, will not be amused. You could also snap the tongue dolly off quite easily.
With all of this in mind, my guess is that you would try this arrangement about a half dozen times, before you would become unhappy with it.
But, assuming that you want to try it, think about the investment. Since the actual weight of your trailer and jetskis is about 1,500 pounds, and you need to account for a margin of safety, you will need a Class II (3,500 lbs) receiver hitch for your car. That will cost you about $150 - $200 without installation. With installation, it will be about $300.
You will also need an ATV winch of about 2,500 to 3,000 pounds capacity. There are manufacturers (Warn, for one), who make ATV winches of lesser capacity, but they tend to drop from 2,500 lbs down to 1,500 lbs, which isn't suitable, because it offers no margin of safety given your load. This is why I specified a Class II hitch rather than a Class I (2,000 lbs) hitch. This winch will cost you about $250 to $450, at least for a decent one. You will also have to buy a multimount bracket with a drawbar. Cost for this is likely to be about $100 to $150.
Next on the list will be wiring. If you need to have it done by someone else, plan on a minimum of $100.
So, now we are at a minimum of $500, if you buy the cheapest gear and do all of the installation yourself. If you buy better quality and have pros put it all together, your cost will be about $1,000.
I think that if you consider all of this, the potential for spending a bunch of money that you will end up regretting, is high. If it were my choice to make, I'd go on a hunt for an old S10 or Toyota pickup that is mechanically sound, even if it did have a "terminal case of the uglies." These vehicles can be picked up for very little and aren't that expensive to insure/operate, if they are only used for weekend trips to the ramp.
PS: If you mount a winch on the trailer, you will have to either mount a large battery to the trailer also, or run a cable to the car. Since a winch will tend to draw a fair amount of power, plan on buying a good sized battery at about $80 to $120. To me, powering off the car is a better choice, because you can leave it running to lessen draw from the battery. If you do this, however, consult an electrician or some other knowledgable person, in order to determine correct wire size - a long cable run to power a winch is going to result in resistance issues, if you don't go to a high enough guage.